UVA/UVB
There are three different types of UV radiation – UVA, UVB and UVC – which are classified based on the length of their waves.
UVC, with the shortest wavelengths, is completely absorbed by the ozone in the earth’s atmosphere and is therefore of little concern. Both UVA and UVB can break through the ozone layer and reach the ground and are responsible for skin damage and skin cancer. UVA (with the longest wavelengths) can penetrate deeply and damage the skin’s lower layers. UVA is responsible for sunburn, wrinkles, freckles, suntan, precancerous skin conditions, and skin cancer. UVB (with medium wavelengths) can damage the skin’s outer layer and cause sunburn and skin cancer.
A helpful rule of thumb is: “A (UVA) is for aging, B (UVB) is for burning.” Check out the diagram below for better understanding of UVA and UVB.
